Last year part of my daughter’s schoolyard was landscaped and fitted with new entertainments. The landscapers also built a stone circle right next to her classroom. (I attended that school myself in 1982-85. The building in the background was the council dentistry clinic where I was fitted with braces.)
Structures like these are known as domarringar, “judge circles”, in Swedish archaeology. They’re Early Iron Age grave superstructures dating from c. 500 BC to AD 500, each usually with a cremation urn buried somewhere inside the circle. The term “judge circle” comes from recent folklore (or antiquarian speculation?), which held that judicial assemblies once convened at sites like these, with one member sitting on each stone. I don’t know how old that idea is.
A number of details show that the judge circle at school doesn’t belong to their main period of construction. Firstly, when (rarely) there is a central stone in the Iron Age structures, it’s just one, not two. Secondly, while the Iron Age ones are pretty much perfectly circular and were probably drawn up with a central pole and a rope, the one at school is irregularly oval in outline. And finally, with twelve stones in the circle, the one at school doesn’t conform to Early Iron Age numerology.
Intact Iron Age judge circles have 7, 9, 11, 2*7, 2*9 or 2*11 stones. The same numbers recur in the knobs on amulet rings that women in certain regions wore in the 5th and 6th centuries. There’s at least one case where an amulet ring has been found in a judge-circle burial. The most common number of knobs is nine, and I’ve suggested that it might have something to do with the months of pregnancy.
Archaeology aside, Juniorette tells me that the school stone circle is quite popular, as can be seen from the absence of turf inside the circle. She describes three different games you play with it according to the number of available participants. One is named “The Singing Giant”.